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fortunately

Originally Posted by BEinIN

I can just picture the waitress or bar maid standing in front of your table with a disintrested look on her face whilst you attempt to sketch a fleeting thought on a soggy napkin with the pen or pencil you've barrowed from her.

"What is beautiful is simple, and what is simple always works"....Kalashnikov, inventor of the AK-47.
Currently bikeless, but looking hard! "Center yourself in the vertizontal. Ride a motorcycle...namaste' "

kbasa: I could load a disk with development sketches that plot the course of this result !

That has to be one of the most elegantly designed frames I've ever seen! Torsional rigidity will be the rule of the day! If there are any Motorrad engineers seeing this from the old days I bet they're saying "Why didn't I think of that!"

I personally think you should paint the frame a contrasting color from the rest of the motorcycle to highlight it. If the bike is going to be black, paint the frame red like a Ducati.

thanks: kreinke, ultracyclist, & ljr5487 !

[QUOTE=kreinke;277379]That has to be one of the most elegantly designed frames I've ever seen! Torsional rigidity will be the rule of the day! If there are any Motorrad engineers seeing this from the old days I bet they're saying "Why didn't I think of that!"

Many reasons would complicate the use of such a frame in production. Starting with construction cost, packaging of all the components necessary for legal road use would be another, and finally, the market ΤΗτ how many traditional BMW riders would be interested ? (the R1200S was introduced, and the market asked: where's the panniers ? the SO says the back seat isn't comfortable ΤΗτ the model is not a big seller... Oddly, I own one).

In the late 1960's when the Type247 frame was introduced, design criteria was quite different. The demands of a 60hp engine, tire & braking technology available, and the status of knowledge regarding chassis design and dynamics formed the result. Also, in all fairness, the engineers chose as a design goal, a 'flexible' frame that would perform equally as well on ALL kinds of ROAD SURFACES, as opposed to one that would work best on the race-track. By the early '80s, BMW was looking to discontinue the Boxer, and, as a consequence, development curtailed. (remember the R1 concept ?)

I'm sure the engineers were aware of 'what could be done', and designed what best suited the 'needs' as defined by production and market demands. (although that may be optimistic ΤΗτ since Udo Gietl patently rejected the special race frames provided by the BMW factory in the early '70s after a few outings, and hired Rob North to design one that actually 'worked'...)

The frame designed by Rob North and raced by Butler-Smith in the late '70s was as similar to my design as yesterday's technology allowed, and (at least superficially) quite similar at that.

I'm sure that with todays laser cutting and hydroforming technology this frame would be economical to produce. If it succeeds I hope you have the gumption to blueprint, and sell these frames. Surely there's a machine shop with a laser cutter or waterjet that would take on the task.

market

Originally Posted by kreinke

I'm sure that with todays laser cutting and hydroforming technology this frame would be economical to produce. If it succeeds I hope you have the gumption to blueprint, and sell these frames. Surely there's a machine shop with a laser cutter or waterjet that would take on the task.

I see a real market in the "custom cafe racer" segment.

LOL. I know that market pretty well ! I also know of several concerns in Europe that DO market race frames and 'performance packages' that include frame upgrades or custom frames. (visit my web-site http://www.rockerboxer.com to know what is available).
Consequently, I know the costs involved for a limited production and what the quite focused 'old BMW custom cafe segment' might be willing to spend ...

Body Pieces Arrived

Yam TZ125 seat-base and a Duc F1 upper fairing arrived UPS from Airtech Streamlining today. these two pieces, and a Laverda 750 SFC style aluminum gas tank hammered out by Evan Wilcox will be the sum total of body-work for the OldCro project.

OldCro tango

There's always a demon lurking somewhere in the shadows to thwart the best of plans and attempts ! No project runs to completion without glitches, eh ? The front shock mount worked perfectly with the donor-Duc-mock-up shock ... Not so with the first Ohlins intended to replace it ΤΗτ interference with the perpendicular reservoir. Not so with the second ΤΗτ parallel reservoir and adjusters, but still a poor fit ...

so the entire back of the frame comes off ...

new brackets made ...

frame rails re-cut and re-placed ...

and, finally, we are back on track to "make it right" and just about almost to that stage of finish ... where we were 2 weeks ago ...

I thank "the gods of speed" that Randy is a patient man and a consummate professional.